A man stabbed at least eight people Tuesday at a shopping mall in the South Korean city of Incheon, authorities said, with one victim sustaining life-threatening injuries. The 59-year-old suspect was subdued by business owners and bystanders before law enforcement arrived, according to officials from Incheon’s Namdong District police station and local witnesses.

The attacker reportedly moved through the mall, stabbing individuals on multiple floors. Witnesses described the man as having knives tied to both hands, attacking people in various locations as he traveled up and down the mall on escalators. One bystander, Nah Hyun-joon, recounted that the assailant assaulted several people in a second-floor food court before moving to the third floor, where he stabbed at least one woman. Nah said the attacker then proceeded toward a movie theater on the fourth floor but was stopped by several individuals who blocked his path with chairs at the top of an escalator.

South Korea’s Justice Ministry indicated that the suspect had a prior record of violent offenses and mental illness and was required to wear an electronic monitoring anklet at the time of the attack. In line with the country’s standard legal procedure, officials have not released the suspect’s name.

Investigations are ongoing as authorities seek to determine the motive behind the attack and assess the condition of the victims. The incident has heightened concerns over public safety and mental health monitoring in South Korea.